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/*
* Based on arch/arm/lib/strnlen_user.S
*
* Copyright (C) 1995-2000 Russell King
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/errno.h>
.text
.align 5
/* Prototype: unsigned long __strnlen_user(const char *str, long n)
* Purpose : get length of a string in user memory
* Params : str - address of string in user memory
* Returns : length of string *including terminator*
* or zero on exception, or n if too long
*/
ENTRY(__strnlen_user)
mov x2, x0
1: subs x1, x1, #1
b.mi 2f
USER(9f, ldrb w3, [x0], #1 )
cbnz w3, 1b
2: sub x0, x0, x2
ret
ENDPROC(__strnlen_user)
.section .fixup,"ax"
.align 0
9: mov x0, #0
ret
.previous
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